The island marble is white and greenish in color, with a marbled texture under the hind wing and a wingspan of approximately 45 millimeters.

SAVING THE ISLAND MARBLE BUTTERFLY

A beautiful white and green butterfly with a marbled hind wing, the island marble once fluttered about in the open grasslands and Garry oak woodlands of Washington's San Juan Islands and Canada's Gabriola and Vancouver Islands. Last seen in 1908, it was believed extinct until a small population was found 90 years later in the San Juan Island National Historical Park. Scientists believe this is the only viable population of island marble butterflies in the world — one catastrophic event could wipe out the whole population.

In 2002, the Center for Biological Diversity, along with the Xerces Society, Northwest Ecosystem Alliance, and the Friends of the San Juans, petitioned the U.S. Fish and Wildlife Service to list the island marble butterfly as an endangered species under the Endangered Species Act. Although the Act requires the Service to determine if a species is indeed endangered within a year after a petition is submitted, no action was taken for the island marble until 2004, when the Center and its partners sued the Service to respond.

The Service finally took action in February 2006, acknowledging that the petition was warranted and beginning a review of the butterfly's status. But in November 2004, the Service denied the petition, concluding that the butterfly does not require protection. The agency claimed that enough populations of the island marble existed to justify its listing denial, but scientists argue that only one of these populations is viable.

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